Manufacture of cordage



Patented Aug. 16, 1927.

v UNITED. STATES PATENT OFFICE.

WARREN K. LEWIS, 0F NEWTON, MASSACHUSETTS, ASSIGNOR TO SAMSON COBDAGE WORKS, 0F BOSTON, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

MANUFACTURE OF COBDAGE.

No Drawing.

similar threaded material, and it will be herein disclosed in connection more particularly with the manufacture of sash cord, it

' being understood, however, that the invention is also applicable to the manufacture of other forms of cordage .and that the term cord is herein used in a generic sense to include any form of cordage to which the process may be applied.

It is the chief object of the inventionto improve the wearing qualities of sash cord and other forms of cordager The life of sash cord as ordinarily used is limited chiefly by thefrictionof the fibres of the cord on each other as the cord runs overthe pulleys in the window casings. Such cord is, however, used for other purposes, as for instance, clothes lines, log lines, and the like, and here the exposure to weather is also an important factor in limit ing the life of the cord. In order to reduce the friction in the cord and to render it more resistant to weather, it has been proposed heretofore to impregnate it with a lubricating agent, the lubricant being carried intothecord by a solvent; This process, however, has not proved satisfactory for several reasons, among which may be mentioned particularly the difficulty in controlling the quantity of lubricant so introduced, the disagreeable appearance given to the cord by this process, and the excessive expense which it involves.

The present invention aims, therefore, to improve the processes of impregnating cord with a lubricating material with a view especially to rendering such processes more economical, controlling more accurately the quantity of lubricant introduced, and producing a cord having the desired appearance.

The ordinary process of manufacturing braided sash cord consists in braiding a series of strands around a central core strand which usually is twisted. .All of these strands usually are made of cotton. I have found that the objects above mentioned maybe realized very conveniently in a cord of this type by loading the core strand with a lubricant, then proceeding with the braiding operations in the'usual manner,and after the cord has been completed, heating it sufficiently to diffuse the lubricant car- .erations of econom Application filed September 20, 1924. Serial No. 738,964.

ried by the core throughthe surrounding d braided strands. 1

Any one of a variety of lubricating ma-- terials may be used for this purpose such,

for example, as paraflin oil, paraflin wax, 'japan wax, and numerous other waxes, greases, and oils, I prefer, however, from consid' and appearance, to use paraffin-wax. he central core strand may be saturated with this material very convenientl by running it through melted paraffin. his wax is' hard at normal temperatures so that its. use is not objectionable in performing-the usual braiding oper ations, and it melts at a low temperature and is readily absorbed. by the cotton, so that it penetrates quickly through the braided strands when the cord is heated. The color also is agreeable. The heating step'usually consists simply in-running the cord through an oven heated to, say 175 to 200 F.

It is. customary to apply a finish coat of sizing to a sash cord, and this coatin operation may be performed either be ore or after the cord is heated. An important advantage of this process is that the difiusion of the wax throu h the cord, as above described, does not ave any injurious effect on the finish coat when applied in the usual I manner so that the impregnated "sash cord presents the appearance to which the trade is accustomed and which it demands.

The paraffin wax efiectually lubricates the fibres or strands of which the cord is com posed and it therefore reduces very materially the friction which is usually responsible for wearing out the cord. At the same time, the wax renders the cord far more resistant to the weather than it would be otherwise so that it materially improves the serviceability of the cord when it is to be used for log lines, clothes lines, or the like. The wax is inexpensive and the process above describedis very economical to practice, as will be obvious.

'By saturating the core strand with the paraflin wax or other lubricant which is since this strand runs fairly uniform in size, the quantity of Wax that will be absorbed by it per foot is also uniform. The quantity of wax introduced in each foot of sash cord, therefore, is easily and accurately controlled. It may here be mentioned, also, that since the wax, when melted, is diffused by capillarity, and since the cord is of fine structure this force is relatively great and the distribution of the was, therefore, is substantially perfect.

l/Vhen the cord is. fabricated in some other manner, as by twisting, the same general process of impregnation may still be followed. If the cord is of small size itcan be satisfactorily impregnated by saturating one of the strands before it is twisted together with its companion strands, and the lubricant can'then be diffused through the latter strands by running the cord through an oven. In some cases it may be necessary to load more than one strand with lubricant in order to distribute this mate rial more uniformly in the cord and to facilitate its penetration into those strands which are not loaded with it. I

I have definitely determined that the serviceability and length of life of a cord impregnated as above described is immensely increased. The invention is especially valuable the manufacture of sash cord because of the peculiar service required of this material. 7

Having thus describedmy invention, what I desire to claim as new is:

1. The herein described process which consistsin fabricating a. cord from a plurality of strands of material, at least one of Which "is loaded with a lubricant,

while others are not so loaded, and subsequently diffusing said lubricant substantially through the adjacent strands.

2. The herein described process which consists in fabricating a cord from a plurality of strands of material, a limited number of which are substantially saturated with lubricating material, and subsequently treating. the cord to cause said. lubricating material to penetrate the strands which are not initially saturated with it.

3. The herein described process which consists in fabricating a cord from a plurality of strands of material, one of which carries a quantity of waxy lubricant suflicicnt to impregnate the others, and subsequently treating the cordto cause said lubricant to penetrate the strands which are not loaded with it.

4. That improvement in the process of making a braided cord which consists in braiding a series of strands around a central core loaded with a waxy material, and subsequently heating the cord to cause said material to'be absorbed by said strands.

5. That improvement in the process of making a braided cord which consists in braiding a series of strands around a central core saturated with a lubricant, and subsequently heating the cord so braided to diffuse the lubricant substantially through said strands.

6. That improvement in the process of making a braided cord which consists in braidin a series of strands around a central core saturated with paraifin wax, and subsequently heating the cord so braided to diffuse the wax through said. strands.

lVARREN K. LEWIS. 

